by Ellen Whinnett in London and staff writers News Corp Australia Network

THE British government will introduce "straightforward" legislation within days, seeking parliament's approval to trigger Britain's divorce with the European Union, Brexit minister David Davis said overnight.

Earlier the UK Supreme Court ruled that Prime Minister Theresa May must give parliament a vote before she can invoke Article 50 of the EU's Lisbon Treaty to begin two years of exit talks.

"We will within days introduce legislation to give the government the legal power to trigger Article 50," Mr Davis told parliament.

"This will be the most straightforward bill possible to give effect to the decision of the people and respect the Supreme Court's judgment."

Ms May had been trying to avoid a Parliamentary vote, fearing MPs opposed to Brexit would delay and amend the process.

SCOTT MORRISON CALLS FOR CALM

It comes as Australian Treasurer Scott Morrison, who is in London for a series of meetings, called for a calm approach to the Brexit negotiations.

Mr Morrison said people needed to take a "pragmatic'' and "shared'' approach on the key financial issues to be resolved through the negotiations.

"Our view is that this is the decision made by the British people and now there are practical issues to be addressed,'' he told Bloomberg.

"They are incredibly detailed and complex issues around transitions and on settlement of the euro and issues around passporting for financial institutions here in the UK."

Passporting is the term used when banks can provide services to people in other countries by offering them from their home country base.

Mr Morrison yesterday met British Chancellor Philip Hammond, and is shortly heading to Germany for further talks with G20 members.

"It's in everybody's interests that all of these things get sorted out in a very pragmatic and patient way,'' he said.